by Brian Truitt, USA TODAY

by Brian Truitt, USA TODAY

The English actor's Pacific Rim character Raleigh Becket has a certain confident gait when getting ready to take a giant robot Jaeger into war against futuristic monster Kaiju.

And that character shares it with Hunnam's chronically troubled biker-club president Jax Teller on FX's Sons of Anarchy.

The walk isn't a trait of those roles, though - it's a part of Hunnam's strong personality born out of being from a working-class, rough-and-tumble hometown.

"People from Newcastle are called Geordies, and where I grew up was a battleground," says Hunnam, 33. "If you couldn't fight, you were dead. The walk was almost like the warning - an attempt to project 'You fight me, it's going to be all bad for you.' ''

A serious tone turns lighthearted with a laugh. "I've been swaggering since I was 14 years old!"

Pacific Rim (opening wide Friday) takes Hunnam from the small screen of cable dramas to Hollywood leading man as the central character in Guillermo del Toro's sci-fi monster mash of attacking sea creatures from another dimension and the mechanical weapons that mankind has built to stop them.

Kaiju are just one of Raleigh's problems, though. Some years after his brother is killed in a Kaiju attack, the Jaeger pilot gets his groove back and a rookie co-pilot (Rinko Kikuchi) to take the Gipsy Danger robot back onto the global battlefield.

"If the audience is engaged in the story, it can only be through the character of Raleigh because he's the hero, he's the guy who transcends his own limitations and steps up when no one else has the tools," says Ron Perlman, Hunnam's co-star in Pacific Rim and on Sons of Anarchy. "With Charlie, you're going to get a guy who'll give you the look and dedication and skill set you need to pull that off."

Del Toro originally had considered Hunnam for the role of a villainous albino prince in his 2008 sequel Hellboy II: The Golden Army. The director says he didn't look quite right in all the makeup, yet it might have been for the best in terms of personality, too.

"Charlie has a very, very transparent decency," del Toro says. "He has a good-guy aura, which is very hard to simulate."

Pacific Rim needed a heroic effort behind the scenes for Hunnam as well, with the contraptions he had to wear as a Jaeger pilot. The suit looked cool before he put it on. But the actor's attitude changed once he had his boots strapped onto a raised stage of hydraulic presses and into a skintight snug harness. The latter contraption kept him from breaking his ankles but it was torture on, well, his more sensitive parts.

"It was really, really brutal to operate it," Hunnam recalls. "It was ostensibly an elliptical machine, but whilst wearing a suit that weighed 40 pounds and doing it for 14 hours a day six days a week for four weeks. The kid-like enthusiasm and awe quickly evaporated into just sheer survival."

Still, he's used to struggle, both physically and mentally, going back to his British roots.

"My main problem is that I'm perpetually on the cusp of complete existential crisis, and that's why I act," Hunnam says with a chuckle. "I grew up in a pretty socially and economically depressed place. I felt really conscious as a very, very young man - like 7 or 8 - that everybody was just so caught up in survival and the drudgery of just getting through the day.

Acting looked appealing because "I just felt like I needed to find something that was going to be at least significant for me in my life."

As a child he felt most happy while watching movies such as Star Wars and Little Shop of Horrors, moments that transported him to another world and away from feeling crazy or lost, Hunnam says. "I thought if I could be a part of that, then my life might make some kind of sense.

"I've always dreamed of being a leading man," he adds, "but only because the leading man gets to do a lot of great work - not because I ever was interested in being famous. To me, it's all about storytelling and being part of something I feel strongly about and feels important to me."

His next film, the del Toro-directed Crimson Peak that begins filming in January, is a gothic haunted-house movie where Hunnam plays "a very quite, thoughtful, learned, stolid gentleman who doesn't get the girl and who isn't suave or slick or swashbuckling in any way."

In other words, not a guy with an abundance of swagger.

"The Geordie walk is going to be shelved for this," Hunnam says. "That's one of the things I'm most eager to experiment with on the physical side of it. I have to find the way this guy walks. I'm going to tell Guillermo, 'You've gotta keep me honest. Don't let the Geordie walk in.' "